3636993981 has 8 divisors (see below), whose sum is σ = 4856686560. Its totient is φ = 2420982032.

The previous prime is 3636993967. The next prime is 3636994043. The reversal of 3636993981 is 1893996363.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 3636993981 - 2⁵ = 3636993949 is a prime.

It is a super-2 number, since 2×3636993981² = 26455450435660456722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3636993781) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 917850 + ... + 921803.

It is an arithmetic number, because the mean of its divisors is an integer number (607085820).

Almost surely, 2^3636993981 is an apocalyptic number.

It is an amenable number.

3636993981 is a deficient number, since it is larger than the sum of its proper divisors (1219692579).

3636993981 is a wasteful number, since it uses less digits than its factorization.

3636993981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1840315.

The product of its digits is 5668704, while the sum is 57.

The square root of 3636993981 is about 60307.4952306925. The cubic root of 3636993981 is about 1537.8507688549.

The spelling of 3636993981 in words is "three billion, six hundred thirty-six million, nine hundred ninety-three thousand, nine hundred eighty-one".